As opposed to open surgery in which a surgeon cuts a relatively large incision in the skin of a patient for accessing internal organs, minimally invasive surgical procedures are performed by making relatively small incisions and then inserting tools through the incisions to access the organs. Minimally invasive surgery usually results in shorter hospitalization times, reduced therapy requirements, less pain, less scarring, and fewer complications.
Although minimally invasive surgical procedures involving small incisions include many advantages over open surgery, minimally invasive surgery can still create challenges to a surgeon. For example, the surgeon must typically rely on a miniature camera introduced through an incision to view the patient's internal organs and see how the movement and operation of the tools affects the organs. The camera transmits images to a visual display, allowing the surgeon to see the internal organs and tissues and to see the effect of other minimally invasive tools on the organs and tissues. In this way, the surgeon is able to perform laparoscopic surgery, dissection, cauterization, endoscopy, telesurgery, and the like.
Compared to open surgery, however, minimally invasive surgery presents limitations in visual and haptic perceptions, and creates challenges unique to this type of surgery. One of the major concerns relevant to both open surgery and minimally invasive surgery is the potential for tissue damage, possibly caused by inappropriate use of force. For example, surgical staplers include a distal end that simultaneously make a longitudinal incision in tissue and applies lines of staples on opposing sides of the incision. The distal end of the surgical stapler includes jaws for clamping or gripping tissue and the user fires the surgical stapler with a single firing stroke, or multiple firing strokes, depending on the device. In both open surgery and minimally invasive surgery, the tissue being stapled is clamped within the jaws of the surgical stapler and is not visible to the user, and therefore direct visualization is not helpful in certain tissue properties relevant to the surgical procedure. Firing the surgical stapler causes severing and stapling of the clamped tissue. In motor-driven surgical staplers, the cutting/stapling operation is actuated by merely pressing a button or firing trigger. However, users prefer to maintain control of deploying the staple and have the ability to stop deployment at anytime if the forces felt in the handle of the device feel too great or for some other clinical reason. Accordingly, there is a need for improved surgical staplers and in particular, there is a need for motor-driven surgical staplers having improved feedback related to the surgical procedure.